Circuit for X-ray multiple-tube stands



June 24, 1930.

J. B. WANTZ CIRCUIT FOR X-RAY MULTIPLE TUBE STANDS Filed Dec. 8, 1927INVEHTOE auuus a. WANTZ ATTORNEY Patented June 24, 1930 UNITED STATESPATENT QFFEE J ULI U's B. WANTZ, or oAK PARK, ILLINOIS, ASSIGNOR 'roVICTOR a CORPORATION or NEW TION, OF CHICAGO, ILLINOIS,

X-RAY CORPORA- YORK CIRCUIT FOR X-RAY MULTIPLE-TUBE STANDS Applicationfiled December s, 1927.

The present invention has to do with electrical circuits and relatesparticularly to a circuit adapted to be used in conjunction with themultiple X-ray tube stand or tube holder, for which application forpatent has been made in the name of Julius B. VVantz and Julius J.Grobe, under date of December 3, 1926, Serial N 0. 152,347. Thisapplication is a continuation in part of the prior application of JuliusB. l/Vantz, serially numbered 169,734 entitled Circuit for X-raymultiple tube stand and filed February 21,

Radiographyhas made tremendous strides within the last two or threeyears. The improvements in tube structure and tube performance haveresulted in finer X-ray photographs than have ever heretofore been made,and the improvements in X-ray apparatus have made it possible to obtainradiographs without guess-work.

Until relatively recently, however, photographs by X-lightwere madeWithout any certainty as to whether the part desired to be shown in theradiograph was actually being photographed.

With the combination screens with the various X-ray apparatus used forphotography and whenmeans for quick change from fiuoroscopy toradiography were installed, the ability of an operator to obtain asatisfactory radiograph was many times multiplied.

One of the principal obstacles which has been met when combiningfluoroscopic screens and radiographic outfits, however, has been thatthe two voltages required, the

of fluoroscopic one for radiography and the other for fluoroscopy, areso entirely different that it is difficult with the ordinary commercialX-ray apparatus to successfully obtain the benefit of a prior orprevious fluoroscopic examina tion for disclosing the proper objectposition for a radiograph. I

Almost'invariably, when the ordinary type of ,X-ray apparatus isemployed, the patient to be photographed will move during the periodadjustments are being made to change the character of the voltage fromthat for fluoroscopy to that for radiography. This aminations or anSerial No. 238,512.

mg a part of the cathode of a tube. This is true whether one tube or twoor more tubes are employed in a single apparatus.

Ordinarily, the high tension voltage impressed upon the electrodes of atube is controlled by an auto transformer. The adjustments in respect tosuch auto transformer are coarse, and may be somewhat quickly obtainedby adjusting the control handle upon a conventional auto transformer,generally contained in a control stand.

But very accurate adjustment is necessary with respect to the voltageimpressed upon the filament of a tube.

An adjustment for the auto transformer for the current impressed acrossthe electrodes may be disturbed frequently because so readilyreobtained. The adjustment for the filament, however, is dilficult toobtain and once determined should seldom be varied. Further, anadjustment for fluoroscopic exadjustment for radiographic work onceobtained for the filament should be maintained, if possible, becausediificult to obtain to an accurate degree and because of the timerequired to procure. Certainly, good practice and economy of timeforbids frequent broad changes of the adjustment required to heat afilament for a fluoroscopic current to an adjustment required inconjunction with the high voltage impressed upon the electrodes of atube for radiographic work. I

The reason for this is the sensitivity of the filament which is so greatthat a very delicate control member or filament current regulator isgenerally employed in well assembled transformer posed.

X-ray apparatus. A great number of turns of the contro handle of such adevice is necessary in order to change it from tl e adjustment employedfor radiography to that neccssary for fiuoroscopy, or vice 'ersa.

The present invention concerns the circuit or circuits to the filamentof a tube, and the objects of the invention are to provide a pluralityof separably maintainable adj ustmeuts for a filament so that inchanging from fluoroscopy to radiography, rather than make a change inthe adjustment of a single unit controlling the intensity of theelectromo vc force applied to the filament, an auxiliary filamentcurrent transformer is brought into play and used in the secondadjustments.

There are number of ways which I have conceived in which circuits may bearranged for .he provision of a multiple adjustment of filament current.The principle of the present invention is the provision of one controlmeans and transformer for the filament having in combination therewith asecond (or third, etc.) control means and transformer whereby a currentof different intensity from that impressed upon the filament through thefirst control means and transformer may be impressed upon such filamentand controlled by such second (or third, etc.) control means andtransformer.

It is quite manifest that a circuit may be arranged with two step-downtransformers. It is equall manifest that two filament current controlmeans may be employed with said *s and obtain the same result as inconwhen a single control means is used junction with two transformers.

There is submitted with his application a single sheet of drawingschematically illustrating a circuit suitable for obtaining the objectsherein described.

In such drawi g, a tube stand is disclosec in plan view. Such standincludes a vertical column l0 upon which a tube holder is dis- The tubeholder ll is counterbalanced by a weight- (nct shown) adapted toreciprocate within the column 10, the cable 12 to such comit-erweightand a pulley 13, over which itpasses, being shown at the top of thecolumn 10.

The multiple tube holc er 11 comprises a main carriage l i swivellydisposed at 15 upon a member 16 movable vertically upon the column 10and ithas side arms 17 terminating in a tie-rod 18. The side arms 17provide tracks for a tube supporting board 19 upon which two -(or more)tubes 20 are mounted, said board being supplied with roller bearings 21at its opposite sides. The tube board 19, therefore, is adapted to bemoved intermediate the main carriage 1% and tie-rod l8 along-the sidearms 17.

The switch S disclosed in the drawing is adapted to be actuated by themovements of the tube board l9, so that when one of the motive forces sodelivered is tubes 20 thereon is in operable position, the switch is inone extreme position, but when the other tube 20 is in operableposition, the switch 5 is oppositely disposed.

At the right hand side of the drawing, one of th high tension conduits22 is shown, and as will be hereinafter pointed out, the other hightension conduit may be also employed as a filament current conduit. Theother high tension line 22" is connected to the cathode and one side ofthe secondary circuit of the filament may be employed for such purpose.

Wherever, hereinbefore or hereinafter heated cathode tube or hot cathodeX- ray tube, or a similar expression is employed, an X-ray tube havingan electrode adaptedto be electrically energized for cont-rollin thepassage of high tension intermediate the two main electrodes of a tubeis intended. Euch an electrode is sometimes referred to herein as anelectron emitting electrode.

Shields 23 are adapted to be used about the tubes 20 as is now common inthe art, such shields being opaque to X-ray light and having the generalcontour of the tube 20 about which they are disposed except for thewindow to allow the passage of X-ray light.

Reference should be had to the first application referred to above foran illustration of a multiple tube holder in a table and in astereoscope device. Such devices have a rotating or sliding tube holderin which the invention may be utilized as well as'in the tube stand hereillustrated.

Generally, from a single source of current, there is adapted to bedelivered at a terminal orterminals adj acentto a sliding or movabletube rack for a plurality of tubes (two as here shown), electromotiveforce of different magnitudes. The invention may readily be adapted tomeet the requirements of other X- ray apparatus, as is apparent. Theelectrofor controlling the X-ray radiation.

In the multiple tube holders here disclosed and as shown in said priorapplication, the Iii-ray tubes are adapted to be moved into position foruse one at a time and shifted as necessity requires. 7 i

Suitable contacts are generally provided in association with the slidingor rotatable tube carrier as the case may be'so that each tube, as itmoves into position,automatically establishes electrical connection withthe circuit to the filament of the X-ray tube in operable position. Thecircuit here described may be substituted for the filament circuit setoutin the prior application referredto;

Means are provided by a multiple position switch,-"or in some othermanner, whereby, as an incident to the movement of one tube, or of thetube rack or holder, here a slidingmovement, the circuit to the filamentterminal is broken and the circuit is reestab the purpose of 1 to ilished at the time a second tube (or the same tube again) is moved intoposition in the stand for use.

The conduits from the alternating current source are indicated 1 and 2.Line 1 runs directly to the regulating members R and A separate conduitruns from each of said regulating members R and R to 0pposite sides ofswitch S. Line 2 runs to the center of the multiple position switchmarked S.

Included in circuit with each of the current control members R and R isa filament current transformer, T and T transformer T being regulated bymember R and transformer T being controlled by member R The secondary ofeach of'the said filament current transformers T and T is directlyconnected to the contacts on the movable tube holder as each tube isbrought into a proper position for use.

By the use of the switch S which is adapted to be automatically actuatedas an incident to the movement of the multiple tube holder,

,, contacts are made and broken in the proper order to provide suitablefilament current for the tube or tubes attached to the multiple holderand about to have high tension impressed thereon.

In one position of the multiple tube holder, current force passesthrough the filament control means R and transformer T while in anotherposition current passes through the filament control member R andtransformer T These two circuits are of different character whereby adifferent potential is delivered through the contacts upon the standengaging the contacts upon the movable tube holder.

Ordinarily one of the two circuits is adjusted for fluoroscopic work andthe other for radiographic work. Of course, more than two tubes and twoadjustments may be provided.

The high potential conduits, 22 and 22 the latter to the cathode of thetube 20, are adapted to be connected to the electrodes of the tubes uponthe tube carrier one at a time by the contacts shown. The latter conduitis closed as an incident to actuation of switch S. Buttons 25 at the endof the anode of the X- ray tubes 20 are adapted to come in contact withthe spring actuated button 24 forming the terminal of the high tensioncurrent conduit 22 shown at the right of the figure in the drawing.

Movement of the tube carrier 19, therefore, brings into play, first, theproper filament current and adjustment for the impression of the properhigh potential by another switch means, and, secondly, adaptability toreceive high tension electromotive force.

Instead of the movement of the multiple tube holder directly actuatingthe filament currentswitch, or the filament current control orregulatory member, the movement thereof may provide a safety device,permitting of the establishment of certain predetermined contacts, theactual contacting being accomplished manually or by means other than themovement of the multiple tube holder 19.

WVhen the invention is used in connection with a stereoscopic shift, thecontacts in the switch S as well as the plunger contacts and both hightension and filament current are likewise adapted to be shifted with thestereoscopic shift.

I claim:

A holder for a plurality of X-ray tubes shiftable to bring such tubesinto operable position one at a time, in combination with means forimpressing an electromotive force of a selected magnitude upon theelectron emitting electrode of each of said X-ray tubes employed, andcomprising a plurality of circuits each including a transformer and aregulatory member, and a switch member actuated by movement of saidholder to select the circuit to the electron emitting electrode of eachseparate tube.

JULIUS B. WVANTZ.

